What IP Address scheme do you use for your Virtual Machines? Are they publicly accessible or are they NAT'd? Do you have only 1 NIC in the server or 1 NIC made available for Virtual Network?
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LukePOct 24 '11 at 16:23

They are publicly accessible. I have only one NIC for the whole server.
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HeinrichOct 24 '11 at 16:43

2 Answers
2

You shouldn't assign other IP addresses to this adapter. Just the one that's used to connect to this host. If your router is configured correctly and forwards the traffic (in bridge mode) to the interface of the NIC in your server (all IP addresses), then assigning the correct external IP address to a virtual machine's vNIC (inside the VM) should do the trick.

So, remove all other IPs from the host NIC (they are useless there), leave only the one you want to use to connect to this host. Assign other IP addresses directly to Virtual Machines.

This does unfortunately not work for me because my data center provider allows only one MAC address for security reasons.
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HeinrichOct 24 '11 at 19:03

2

Find anothe data center provide that understands what virtualization is. Point. Sorry if that sounds snippy, but there is a standard behavior since many years and virtualization is mainstream. I would consider a failure to support that to be basicalyl a breach of standard practices and reason to termainte contrat and invocie them my costs.
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TomTomDec 6 '11 at 15:59

Note: This is obsessively the wrong way to accomplish this in normal situations. The original Question should have contained the abnormal requirement that all External IPs have the same MAC address.
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Chris S♦Dec 6 '11 at 16:43

The use case is real and present. A data center in germany does it that way (Hetzner Online AG, hetzner.de). If you order a subnet, you will not get separate MAC adresses for these IPs
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HeinrichDec 6 '11 at 17:32